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Drilling Holes in Floor Joists for plumbing

I need to reroute a kitchen drain line which involves drilling a hole thru 3 floor joists, what is the rule on the diameter of the hole size in relation to the size of the joist and what is the minimum distance from the edges and the end of the joist where the hole can be so not to effect the structure?

Re: Drilling Holes in Floor Joists for plumbing

Are these solid wood joists or engineered lumber (I-beam style, laminated veneer, or oriented strands)? That makes a big difference.

Also, what are the dimensions of the joists, the length between supporting walls, and the center-to-center spacing?

The "Senior Member" designation under my name doesn't mean I know a lot, it just means I talk a lot.I've been a DIYer since I was 12 (thanks, Dad!). I have read several books on various home improvement topics. I do not have any current code books I can refer to. I was an apprentice plumber for two years.